Electrical transformer



Feb. 28, 1933. -B. J. CHROMY ELECTRICAL TRANSFORMER Original Filed May 23, 1929 l v Patented Feb-'28, i933 UNITED s'rA'rss' PATENT OFFICE I m a. canon, or norx ms, xumssora, assrcnon mo wmsn name, me, or m 1 a v relax, a. Y, a coaroaarrorr or nmwaar:

ELECTRICAL TRANSFORMER Oricinal application fled lav, 1989, Serial No. 885,584. Divided and this application fled 31117 1!,

1930. Serial 10.40am.

My invention relates broadly to electrical apparatus and more specifical y to a transformer and control system operated thereby.

This ap lication is a division of my ap- 5 plication g 1929 for electrical appliances. 'One of the objects of my invention is to provide a construction of transformer ineluding primary and secondary windings and an auxiliary winding where the auxil1ary winding consists of a imetallic strlp capable of expansion and contraction for controlling a switching circuit according to the current induced therein from the rimary winding.

Another object of my invention is to provide a transformer system having means for automatically contro ling the output thereof in proportion to the induced current.

further object of my invention is to provide a transformer system including thermostatic control means for controlling the output thereof.

Other and further objects of m invention relate to the automatically control able transas former construction described more fully in the specification hereinafter following by reference to the accompan ing drawing which diagrammatically i lustrates the transformer system of my invention. so The transformer system of my invention has been illustrated in connectlon with a glow discharge device of the type employed in electric'signs for advertising or other purposes and is caused to flash or flicker in ac- 85 cordance with a predetermined pattern to produce certain desirable and attractive ,efiects.

An electric circuit interrupting mechanism is employed in conjunction with the glow discharge device to connect certain electrodes associated with the device into circuit at predetermined intervals whereby sections of the device are periodically energized and de-enersized. Through the use of this invention a ark spot or portion may be caused to travel along the glow ischarge device whereby a moving effect may be produced in the illuminated sign. Other efiects in which multi-colored glow discharge devices of the intermittently illuminated variety are emerial No. 365,534 filed May 23,

ployed may be produced by using, for example, a luralifty of transparent tubes each filled wit a di erent gas or gases, such as neon, argon, helium, nltrogen, krypton, etc. Gases to which small quantities of readily volatile materials, such as mercury, sodium, potassium, lithium, etc., have been added may also be employed in the glow dischar e display devices made in accordance wit this invention to produce different pleasing and attractive efiects.

While I have shown the transformer system of my invention in associationwith a particular arrangement of glow discharge circuit, it will be understood that any form of load circuit may be employed and that the particular load shown is for illustrative purposes only.

Referring to the drawing a glow discharge tube-37 havin electrodes 37a, 37 b, 370, 37d, 370, etc., has een illustrated as energized through the operation of the transformer 38 and the source connected to winding '40; Y

The transformer 38 which embodies my invention has a primary winding 40, secondary 75 winding 39 and auxiliary secondary winding 42. The winding 42 consists of a bimetallic strip member having the ends thereof interconnected and carrying an extended contactor 43 which sweep over rows of electrical contacts constituting a switching mechanism.

The switchin mechanism includin the short circuited imetallic coil 42 which is coupled magnetically to the primary 40 is provided with an insulated contact supportmg member 42a which moves the contactor 43 into or out of engagement with any pair of a plurality of radially aligned con-' tacts whereby different sections of the glow discharge tube 37 are energized rom selected taps on the secondary winding 39. The normal position for the contactor is in alignment with contact 46 whereupon the relay winding 44 is deenergized and the primary circuit from source 41 remains closed. As the primary 40 of the transformer 38 is energized by the source 41, an electromotive force is induced into the short circuited bimetallic coil 42. The coil 42 due to thermal expansion moves the contactor 43 into succesl Mama. a.

sive engagement with the contacts 46,47, 50, 48 and 49 and circuits established between the main electrode 37a with the electrodes 37c, 37d 37c and 37b successively. The portion of the tube 37 between the electrodes 37a and 370 is thencaused to glow. The unit or auxiliary secondary 42 continues to expand and move the contactor 43 which is insulated from the unit 42, over successive pairs of contacts and cause difierent portions of the tube 37 to glow until the circuit between the contact 49 is. established whereupon the circuit of the relay 44 is energized by the source 45 and the primary circuit of the transformer 38 is opened. Since the transformer 38 is not energized the unit 42 is permitted to cool and return to its original position preparato for a repeat operation. The relay 44 is pre erabl a time delay relay which leaves the 90 circuit of the primary 40 de-energized long enou to permit the unit 42 to return to its original position. That is to say, the relay device 44 has a relatively long time constant and when con- 25 tactor 43 moves to a position, due to thermal expansion of the thermally res onsive strip 42, in which contacts 49 are ridged, the circuit from battery is completed through the winding of relay 44 and after being 80 closed for a sufiicient length of time develops suficient ma etic pull to act upon solenoid 446 against t e action of spring 44a for opening contacts 41a and interrupting the circuit from source 41 to primary winding 40. This annuls the magnetic field from primary winding 40 acting upon the secondary winding formed by thermally responsive strip 42 and permits strip 42 to contract thereby moving contactor 43 counter-clockwise to its initial osition in shunt with contacts 46. Dur- 5 for example in British Patent 167,468 accepted September 7, 1922; German Patent 440,892, dated April 23, 192 5 and United States Patent 1,550,155, dated August 18, 1925. A spring 42a attached to the unit 42 insures rapid and certain return of the movable end of the unit 42 to its pre-energized tion as limited by a stop 42b. It is highly desirable that the contacts 46, 47, 50, 48, 49 etc., are supportedl upon an insulating panelimmersed in oiland the whole transdue to the time constant of theand spring 44a operates to close they 1,see,ero

' but is connected across an auxiliary secondary winding which is coupled to the primary 40 in order that the current through the unit 42 may be properly limited. A resistance or other t pe of current limiting device,such as a c oke coil or a condenser may be connected across the unit 42 instead of directly short circuiting it and if desired these current limiting devices may be made variable.

The auxiliary secondar winding 42 may be inductively coupled with primary winding 40 directly over secondary winding 39 or the auxiliary winding 42 may be disposed in axial alignment with primary winding 40 at one end thereof. Where desired the auxiliary secondary winding 42 may be disposed on one leg of an iron core on interconnected legs of which the primary winding 40 and secondary windin 39 may be mounted. As heretofore pointed out any form of load circuit may be employed with the transformer s stem of my invention and the glow disc iarge tube circuit is merely to be considered in the illustrative sense.

It will be observed that various modifications of this invention may be made without departing from the s irit and scope thereof and that, therefore, do not desire to limit this invention to the exact details as set forth in the foregoin specification except in so far as they are de ned by the ap en ed claims.

What I claim as new and esire to secure by Letters Patent of the United States is as follows:

1. A transformer comprising a primary winding, a thermall responsive secondary winding associated t erewith, a tapped secondary winding cou led with said rimary winding and a switc inlg device carried by a portion of said thermal y responsive secondary winding and adapted to be shifted in position according to the expansion of said thermally responsive secondary winding depending upon the amplitude of current induced therein from said primary for establishing connection with selected ta s on the aforesaid tap seconda winding.

2. A trans ormer comprising a primary winding, a tapped secondary winding inductively related thereto, an inductively associated thermally responsivesecondary winding,

III

means interconnecting the ends of the thermally responsive secondary winding for forminga closed path therethrou h, and a switching device operative u n t e expansion of said secondary win in under the control of current induced therein from said ductively related to said winding for o ration with a load circuit.

3. In a trans ormer system, a primary and secondary winding, a source of energy connected with said primary winding, a load circuit, tapped connections on said secondary winding leading to said load circuit, sets of contacts disposed in each ofsaid tapped connections, an auxiliary secondary winding constituted by a thermally responsive stri member inductivel associated with said primary winding an having the ends thereof connected through a shunt path, an insulated arm carried by said thermally res onsive strip, a contact member supported said insulated arm and adapted to bridgethe individual sets of contacts for successively es tablishing circuits from the tapped connections on said secondary winding to said load circuit and means actuated by said thermally responsive strip member at the limit of move-.

ment thereof for interrupting the circuit betweeen the source of energy and the primary winding for restoring said thermally responsive strip to the initial position thereof.

4. A transformer system comprising a source of otential, a primary winding connected with said source of potential, a pair of secondary windings inductively related to said primary winding, a load circuit, tapped connections for delivering diflerent potentials from one of said secondary windings to a said load circuit, a 1pair of contacts forming an open gap in eac of said tapped connections, the other of said secondary windings comprising a thermally responsive strip inrima'ry winding with a shunt path connected across the terminals thereof, a contact member, means operable according to the thermal action upon said thermally responsive strip to cause said contact member to successively bridge each of the sets of contacts in saidtap ed connec-,

tions for successively de ivering ifierent potentials to the load circuit according to the thermal action of said thermally responsive strip and means actuated by the movement of said thermally res onsive strip to one of its limit ng positions or interrupting the circuit between said source and said primary winding for permitting said thermally responsive strip to be restored to the initlal position thereof.

5. A transformer system comprising a source of potential, a primary winding connected with said source of potential, a pair of secondary windings inductively related to said primary winding, a load circuit, tapped connections for delivering diflerent otentials from one of said secondary windings to saidload circuit, a pair of contacts forming an open gap in each of said tapped connections, the other of said secondary windings comprising a thermally responsive strip inductively related to said primary winding with a shunt path connected across the terminals thereof, a contact member, means operable according to the thermal action upon said thermally responsive strip to cause said contact member to' successively bridge each of the sets of contacts in said tapped connections for successively delivering different potentials to the loadcircuit according to the thermal action of said thermally responsive strip and time delay means actuated by said thermally responsive strip 7 upon movement thereof to one of its expanded positions for interrupting the circuit between said source and said primary winding for a time interval sufiicient to permit said thermally responsive strip to be restored to contracted position.

' 6. A transformer system comprising a tapped connections for delivering different potentials from one of said secondary windings to said load circuit, a pair of contacts forming an open gap in each of said tapped connections, the other of said secondary windings comprising a thermally responsive strip inductively related to said primary winding with a shunt path connected across the terminals thereof, an insulated arm carried by said thermally responsive strip, a contact member mounted on said arm, means operable according to the thermal action upon said thermally responsive strip to cause said contact member to successively bridge each of the sets of contacts in said tapped connections for successively delivering different potentials to the load circuit according to the thermal action of said thermally responsive strip and a relay device having relatively large time constant and operated by move ment of said' thermally responsive strip to its expanded position for interrupting the circuit from said source to said primary winding for a time period sufiicient to allow said contact member to pass over said contacts while said primary winding is deenergized to an initial position'preparatory for a repeat operation when said primary winding is deenergized by-operation of said time delay relay device.

7. In a transformer system for feeding a load circuit, the combination of a primary winding and a pair of secondary windings electromagnetically coupled with said primary winding, one of said secondary windings comprising a convolute bimetallic strip, a switch arm carried by the endof -said bimetallic strip and a multiplicity of contacts connected with certain of the taps on the other of said secondary windings, said switch arm operating to connect selected portions of the tapped secondary winding to the load circuit according to the expansive and contractive action of said bimetallic secondary windmg.

8. A transformer system for feeding a load circuit, comprising a primary winding and a pair of secondary windings inductively associated with said JJrimary winding, one of said secondary win a thermally responsive strip member adapted to change in physical position according to the amplitude of current induced therein from said primary winding,- a switch arm carried by said thermally responsive strip, contacts connected through taps with selected points on the other of said secondary windings, and connections to the load circuit controlled by the movement of said switch arm over said contacts to a position wherein said primary winding is automatically deener gized.

In testimony whereof I aflix my signature.

BEN J. CHROMY.

mgs being constituted by 

